Recently, technology called a wind profiler that measures atmospheric wind direction and wind speed by atmosphere radar is becoming established. With a wind profiler, measuring atmospheric wind direction and wind speed at one-minute to several-minute intervals becomes possible. Atmospheric wind information measured with such high time resolution is useful for improving the accuracy of weather forecasting.
Regarding wind profilers, Patent Literature 1, for example, discloses technology that improves the accuracy of computing wind vectors. The wind profiler in Patent Literature 1 computes Doppler speeds for individual beams and for individual heights from complex received signals, and checks the coherence among the Doppler speeds computed from beams at each height. The wind profiler then selects a combination of beams at each height in order to compute a wind vector on the basis of the coherence among beams, and computes a wind vector for each height using the selected beam combination and the Doppler speed at each height.
Patent Literature 2 discloses a wind profiler signal processing technology that improves the data acquisition rate over a wide height range. In a signal processing device of Patent Literature 2, an optimal incoherent integration time is set for individual heights. A power spectrum is then computed from Fourier-transformed data, and time-integrated for the set incoherent integration time. Additionally, Doppler speeds computed from the incoherent integrated power spectrum are time-averaged, with the low-quality Doppler speed data excluded.